import cfg from './config.js'
var isLetter = (c) => (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')

function CssHandler(tagStyle) {
  var styles = Object.assign(Object.create(null), cfg.userAgentStyles)
  for (var item in tagStyle) styles[item] = (styles[item] ? styles[item] + ';' : '') + tagStyle[item]
  this.styles = styles
}
CssHandler.prototype.getStyle = function (data) {
  this.styles = new parser(data, this.styles).parse()
}
CssHandler.prototype.match = function (name, attrs) {
  var tmp,
    matched = (tmp = this.styles[name]) ? tmp + ';' : ''
  if (attrs.class) {
    var items = attrs.class.split(' ')
    for (var i = 0, item; (item = items[i]); i++) if ((tmp = this.styles['.' + item])) matched += tmp + ';'
  }
  if ((tmp = this.styles['#' + attrs.id])) matched += tmp + ';'
  return matched
}
export default CssHandler

function parser(data, init) {
  this.data = data
  this.floor = 0
  this.i = 0
  this.list = []
  this.res = init
  this.state = this.Space
}
parser.prototype.parse = function () {
  for (var c; (c = this.data[this.i]); this.i++) this.state(c)
  return this.res
}
parser.prototype.section = function () {
  return this.data.substring(this.start, this.i)
}
// 状态机
parser.prototype.Space = function (c) {
  if (c == '.' || c == '#' || isLetter(c)) {
    this.start = this.i
    this.state = this.Name
  } else if (c == '/' && this.data[this.i + 1] == '*') this.Comment()
  else if (!cfg.blankChar[c] && c != ';') this.state = this.Ignore
}
parser.prototype.Comment = function () {
  this.i = this.data.indexOf('*/', this.i) + 1
  if (!this.i) this.i = this.data.length
  this.state = this.Space
}
parser.prototype.Ignore = function (c) {
  if (c == '{') this.floor++
  else if (c == '}' && !--this.floor) {
    this.list = []
    this.state = this.Space
  }
}
parser.prototype.Name = function (c) {
  if (cfg.blankChar[c]) {
    this.list.push(this.section())
    this.state = this.NameSpace
  } else if (c == '{') {
    this.list.push(this.section())
    this.Content()
  } else if (c == ',') {
    this.list.push(this.section())
    this.Comma()
  } else if (!isLetter(c) && (c < '0' || c > '9') && c != '-' && c != '_') this.state = this.Ignore
}
parser.prototype.NameSpace = function (c) {
  if (c == '{') this.Content()
  else if (c == ',') this.Comma()
  else if (!cfg.blankChar[c]) this.state = this.Ignore
}
parser.prototype.Comma = function () {
  while (cfg.blankChar[this.data[++this.i]]);
  if (this.data[this.i] == '{') this.Content()
  else {
    this.start = this.i--
    this.state = this.Name
  }
}
parser.prototype.Content = function () {
  this.start = ++this.i
  if ((this.i = this.data.indexOf('}', this.i)) == -1) this.i = this.data.length
  var content = this.section()
  for (var i = 0, item; (item = this.list[i++]); )
    if (this.res[item]) this.res[item] += ';' + content
    else this.res[item] = content
  this.list = []
  this.state = this.Space
}
